Neonatal Diethylstilbestrol Treatment Research Articles

Altered activation/detoxication enzymology following neonatal diethylstilbestrol treatment.

The effects of neonatal exposure to diethylstilbestrol (DES) on hepatic activation/detoxication enzyme levels in the adult rat were investigated. Neonatal exposure of male rats to DES (DES males) decreased the endogenous levels of UDP-glucuronyltransferase as compared to control males. Female rats exposed neonatally to DES (DES females) had higher endogenous epoxide hydrolase and glutathione transferase activity levels than control females. Adult animals treated neonatally with DES also had altered metabolic potential following exposure to 3-methylcholanthrene and phenobarbital. The DES males treated in adulthood with 3-methylcholanthrene had higher benzo(a)pyrene hydroxylase activities and lower UDP-glucuronyl-transferase activity levels than did control males treated in adulthood with 3-methylcholanthrene. The DES males exposed in adulthood to phenobarbital had reduced cytochrome P-450 and glutathione transferase activity levels as compared with respective controls. The DES females treated in adulthood with 3-methylcholanthrene had lower benzo(a)pyrene hydroxylase and epoxide hydrolase activity levels than control females receiving 3-methylcholanthrene. The DES females challenged in adulthood with phenobarbital also had decreased benzo(a)pyrene hydroxylase, epoxide hydrolase, UDP-glucuronyltrasferase, and glutathione transferase activity levels as compared with respective controls. Our results demonstrated that neonatal exposure to DES changed the endogenous levels of specific hepatic enzymes and altered the metabolic response of these adult animals to a carcinogen and a drug.

Diethylstilbestrol-induced cervical and vaginal adenosis using the neonatal mouse model.

The relevance of diethylstilbestrol (DES) administration to neonatal mice as a model for human pathology attributed to the use of DES in high-risk pregnancies has been investigated, particularly with respect to cervical and vaginal changes in female offspring. Neonatal DES treatment of mice results in tonic pituitary gonadotropin release and continuous estrogen secretion by the ovary. Studies were designed to determine the effect of this altered ovarian endocrine activity on cervical and vaginal histopathology. Ovariectomy of DES-treated mice, with or without estradiol replacement, did not eliminate the lesions, nor did estrogen and progesterone administered in a regimen intended to mimic estrous cycle changes. Induction of the constant estrus state by neonatal estradiol benzoate or testosterone propionate administration or by exposure to constant light did not produce the type of vaginal or cervical changes seen in DES mice. Thus, altered ovarian function is apparently not required for the vaginal and cervical changes appearing in later life. A role for endogenous (or exogenous) ovarian hormones in the developmental progression toward normality is suggested.

Neonatal diethylstilbestrol alters blood pressure and CNS drinking response in SHR and WKY rats.

Neonatal SHR and WKY rats were treated with diethylstilbestrol or propylene glycol (controls). Control SHR had higher blood pressures than WKY rats. Neonatal diethylstilbestrol treatment delayed the onset and full expression of hypertension in the male SHR but had no effect on blood pressure in the other animals. Neonatal diethylstilbestrol treatment had an adverse effect on body weights of male SHR and WKY rats through 98 days of age (not statistically decreased thereafter). Adult female SHR and WKY rats treated neonatally with diethylstilbestrol had body weights significantly greater than the control females. Neonatal treatment with diethylstilbestrol resulted in precocious puberty in female SHR and WKY rats. Control female SHR and WKY rats and female SHR treated neonatally with diethylstilbestrol had attenuated angiotensin - II induced drinking response from the central administration of estrogen in adulthood. The angiotensin II - induced drinking response was not significantly attenuated by central estrogen in adult WKY females exposed neonatally to diethylstilbestrol. Neonatal diethylstilbestrol treatment of WKY female rats appears to have altered neuroendocrine secretions that control CNS drinking behavior.

Neonatal diethylstilbestrol treatment: response of prolactin to dopamine or estradiol in adult mice.

The effects of neonatal diethylstilbestrol (DES) treatment on pituitary PRL response to dopamine (DA) inhibition or estrogen stimulation were studied in C3H/MTV+ mice at 10 weeks, 5 months and 8 months of age using synthesis and release of [3H]PRL by the pituitary as endpoints. In the DA study, anterior pituitaries from ovariectomized or intact, neonatally hormone-treated mice were incubated for 6 h in the presence or absence of DA. In the estrogen study, serum and anterior pituitaries were obtained from ovariectomized neonatally hormone-treated mice injected with oil or 17 beta-estradiol for 7 days before death. Neonatal treatment of mice with 2.5 micrograms/day DES altered basal [3H]PRL synthesis and release as well as circulating PRL concentrations. The results of analysis of variance indicated a significant interaction between the effects of neonatal hormone treatment and DA treatment on [3H]PRL release. Neonatal DES treatment did not alter the response of pituitary PRL to estrogen treatment at the ages examined.

Frequent occurrence of polyovular follicles in ovaries of mice exposed neonatally to diethylstibestrol

The occurrence of polyovular follicles (PF) was examined at 10-34 days of age in the ovaries of BALB/cCrgl female mice given five daily injections of 0.1 microgram diethylstilbestrol (DES), 2 micrograms DES, 100 micrograms progesterone (P), 137 micrograms 17 alpha-hydroxyprogesterone caproate (HPC), 20 micrograms testosterone (T), 20 micrograms 5 alpha-dihydrotestosterone (5 alpha-DHT), or oil vehicle alone starting on the day of birth, and of C57BL/Tw females given five neonatal injections of 1 microgram DES, 20 micrograms 17 beta-estradiol (E2), 50 micrograms 5 alpha-DHT, 50 micrograms 5 beta-DHT, or the vehicle alone. Ovaries of 30-day-old C57BL mice given five daily injections of 1 microgram DES starting at 3-25 days of age were also examined. PF incidence (% of PF per ovary) and PF frequency (% of mice with PF) were significantly greater in BALB/c mice receiving injections of DES, P, HPC, and T than in the controls. In DES-treated mice at 34 days, PF incidence (2-13 oocytes/follicle) was 120-340 times higher than in the controls. BALB/c mice treated with T, P, and HPC showed PF incidence (two to four oocytes/follicle) three- to six-fold higher than in the controls. In 30-day-old C57BL mice treated with T, E2, and DES, PF incidence also increased by two- to 50-fold. 5 alpha-DHT and 5 beta-DHT failed to increase PF incidence. PF incidence was significantly increased only when neonatal DES treatment was begun on days 0 to 3, but was reduced when started at days 10-25.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-Term Responses of the Mouse Uterus to Neonatal Diethylstilbestrol Treatment and to Later Sex Hormone Exposure2

The effects of ovariectomy at 1 month of age and continuous 17 beta-estradiol (E2) and/or progesterone (P) replacement on the uterus of BALB/cCrgl mice neonatally treated with diethylstilbestrol [(DES) CAS: 56-53-1; alpha-alpha'-diethyl-4,4'-stilbenediol] or sesame oil were recorded after 1, 4, 7, and 10 months of treatment. DES-exposed uteri were found to be hypoplastic, less responsive to the growth-promoting effects of E2, and more likely to develop smooth muscle abnormalities after continuous hormonal treatment than similarly treated control uteri. Neonatal DES treatment led to leukocytic infiltration, disruption in the organization of the inner circular smooth muscle layer, and development of a population of epithelial cells believed to respond to later E2 treatment by proliferation and stratification (squamous metaplasia). Qualitative and quantitative responses to continuous P treatment and the development of cystic glandular hyperplasia and adenomyosis were found to be unaltered by neonatal DES administration. The relevance of these results to the problems of uterine abnormalities observed in women exposed to DES in utero is discussed.

3-Methylcholanthrene: Transient Inhibition of the Lytic Step of Mouse Natural Killer Cells<xref ref-type="fn" rid="FN2">2</xref><xref ref-type="fn" rid="FN3">3</xref>

Female mice belonging to NMRI stock were inoculated neonatally with daily doses of 5 micrograms diethylstilbestrol (DES) or olive oil for the first 5 days after birth and in adult life with 20 or 100 micrograms 3-methylcholanthrene (MCA) or the vehicle tricaprylin only. The cytotoxic activity of spleen natural killer (NK) cells against YAC-1 target cells was studied in a 51Cr release assay at 2, 5, 10, or 15 days after the MCA injection. A dose of 20 micrograms MCA to neonatally olive oil-injected females did not influence the NK activity, whereas an injection of 100 micrograms MCA significantly depressed the NK activity to about half the value seen in controls. This suppression was transient, and the normal level was reached again 15 days after the injection. The depressed NK activity could not be related to humoral or cellular suppressor mechanisms. A study at the single-cell level revealed that the inhibition was due to interference with the lytic step of the NK cell without affecting target-binding capacity. In vitro exposure of spleen cells from MCA-treated animals to interferon fully restored the NK activity. Neonatal DES treatment resulted in a depressed NK activity in adult females to a level about half of that seen in olive oil-injected controls. The NK activity in DES-treated females was not influenced by either 20 or 100 micrograms MCA. The MCA-induced suppression of NK activity was discussed in relation to the earlier reported difference in incidence of MCA-induced sarcomas between DES-treated and control females after they were given 20 micrograms MCA in adult life, as well as in relation to the same incidence in the 2 groups treated with 100 micrograms MCA. The results are compatible with a significant role for NK cells during MCA carcinogenesis and indicate that a possible part of the tumorigenic effect of MCA is its early suppressive effect on NK cell activity.

Binding and retention of estrogen in the uterus of hamsters treated neonatally with diethylstilbestrol

We have shown previously that postpubertal estrogen exposure promotes the development of uterine tumors in hamsters treated neonatally with diethylstilbestrol (DES). The purpose of this study was to determine if the uterine estrogen receptor system of adult hamsters was altered after neonatal DES treatment. There was no effect on the concentration, subcellular distribution, apparent binding affinity, sedimentation properties, surface charge characteristics or ligand specificity of uterine estrogen receptor in ovariectomized, estrogen-replaced animals. Furthermore, neonatal DES treatment had no effect on the subcellular distribution of radioactivity in the uterus of adult animals ovariectomized 1 week before challenge with [ 3H]-estradiol-17β(E 2). However, the amount of radioactivity taken up and specifically bound within the uterus 6 h after [ 3H]-E 2 challenge was less in DES-treated compared to control animals. Six hours after challenge with unlabeled E 2, the concentration (pmol/g tissue) of occupied but not total nuclear estrogen receptor was reduced in DES-treated animals. The difference in uterine radioactivity levels and occupied nuclear receptor retention appears to be due to a difference in estrogen metabolism since the systemic concentration of authentic [ 3H]-E 2 was lower in DES-treated animals compared to control. These results demonstrate no DES-induced change in the physicochemical or functional properties of the uterine estrogen receptor system, suggesting that a lesion in this receptor system is not involved in the etiology of uterine tumor development following neonatal DES exposure. However, the DES-treated animal appears to have an enhanced estrogen metabolism.

Neonatal treatment with testosterone proprionate or diethylstilbestrol alters sex differentiation of 5α-reductase and 16α-hydroxylase

Neonatal exposure to testosterone appears to determine the normal programming of certain hepatic enzyme activities, perhaps via the aromatization of testosterone to estrogens in the brain. These studies examine whether neonatal exposure to testosterone propionate (TP) or diethylstilbestrol (DES) alters the normal programming of hepatic 16α-hydroxylase (using [4- 14C]-androstenedione as substrate) or 5α-reductase (using [4- 14C]-testosterone as substrate). In normal adult rats, 16α-hydroxylase is higher in male liver, while 5α-reductase is higher in female liver. Neonatal administration of TP or DES to intact animals produce decreases in adult male 16α-hydroxylase (feminization). Levels of 16α-hydroxylase in resultant adult females and 5α-reductase activity levels in adult male and female rats were unaffected by neonatal TP or DES treatment. Treatment of neonatal rats with DES but not TP results in significantly reduced circulating androgen levels. Therefore, feminized levels of 16α-hydroxylase do not correlate with serum androgen levels. Neonatal castration of male rats on day 1 results in feminization of 16α-hydroxylase and 5α-reductase activities in adult animals. TP or DES treatment on day 2 did not reverse the effect of neonatal castration. These studies demonstrate that the hormonal regulation of the hepatic steroid metabolizing enzymes, 5α-reductase and 16α-hydroxylase, is different. 16α-hydroxylase appears to be more sensitive to neonatal hormonal modulation than is 5α-reductase.

Long-Term Effects of Neonatal Estrogen Treatment on Mitogen Responsiveness of Mouse Spleen Lymphocytes<xref ref-type="fn" rid="FN2">2</xref>

Neonatal female NMRI mice were given injections of olive oil (controls) or daily doses of corticosterone (10 micrograms), 17 beta-estradiol (10 micrograms), or diethylstilbestrol (DES) (0.01, 0.1, 1, or 5 micrograms) for the first 5 days after birth. The 5-micrograms dose of DES resulted in a persistently reduced in vitro mitogen response to concanavalin A or bacterial lipopolysaccharide of spleen lymphocytes from 6-, 10-, and 18-week-old or 17-month-old females. DES injections from day 6 through day 10 did not influence the later mitogen response. Treatment of ovariectomized 10-week-old females with 5 micrograms DES for 5 days resulted in a tendency to a reduced mitogen response (not statistically significant) 24 hours after the last DES injection. Four weeks later, the mitogen response was the same in experimental and control females. Different possible mechanisms for the persistent effect on the mitogen response are discussed. Neonatal DES treatment not only resulted in persistent changes in the cervicovaginal epithelium and in the hypothalamic-pituitary gland control system but also in the spleen lymphocyte mitogen response. The altered mitogen response should be a stimulus for a detailed analysis of the immune system in women exposed to DES during fetal life, some of whom develop later in life clear cell adenocarcinoma of the uterine cervix and vagina.

Adenosis-Like Lesions and Other Cervicovaginal Abnormalities in Mice Treated Perinatally With Estrogen<xref ref-type="fn" rid="FN2">2</xref>

Female mice from three inbred strains (BALB/cCrgl, C3H/Crgl, and C57BL/Crgl) and one noninbred stock [RU:NCS (RU)] were treated perinatally with estradiol benzoate (EB), diethylstilbestrol (DES), or sesame oil and were killed on postnatal days 30--36. A combined prenatal and neonatal regime of EB injections resulted in the abnormal presence of columnar epithelium in the vaginal fornices of some of the mice from each strain or stock. The same epithelial abnormalities were also present in the vaginal fornices of 30-day-old RU:NCS(RU) mice that had been treated only neonatally with EB or DES. The incidence of these lesions was 40--67% in the mice treated prenatally and neonatally with EB, 68% in the neonatal EB treatment group, and 100% in the neonatal DES treatment group. The columnar cells were arranged either as single layers in areas of the fornical lining epithelium or as glandlike or cystic structures in the subepithelial stroma. No cells of this type were detected in any of the samples from sesame oil-inoculated control mice. No comparable epithelial lesions were detected in the common cervical canal of the perinatally estrogen-treated animals, but this treatment consistently resulted in gross structural abnormalities at this site.